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Abstrakt

Functional urban areas (FUA) have became an important component of polycentric settlement structure of all European countries. FUAs have been defined as labour market basins, composed on large city and its surrounding areas (commuting zones). The very spatial and economic concept formed the foundation of old industrial regions. Old industrialized regions with all the spatial challenges and economic problems could be also perceived as a specific type of functional urban area. In Poland, National Spatial Development Concept 2030 (NSDC 2030 2013) describes restructuring and revitalization of degraded areas and cities in terms of spatial policy measures addressed to the supporting of cohesion in problematic areas. That is why integrated revitalization programs of functional urban areas may become key instrument of regional spatial policy and urban strategies. In response to the problems of degraded land and related land-use conflicts, it can significantly help in establishing valuable solutions, as well as ensuring connections between environmental, social and economic needs in the development of functional urban areas.
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Abstrakt

Due to the significant role of macrophytes in the functioning of lake ecosystems studies have been undertaken to examine whether mutual dependence is present within emergent, floating-leaved, and submerged aquatic macrophytes. The study included 5 small lakes from Polesie Lubelskie region. The research included: qualitative analysis of macrophytes (area occupied by macrophytes, composition, range of individual plant groups of occurrence), quantitative analysis of macrophytes (biomass of macrophytes inhabiting the lake), analysis of distribution as well as characteristics diversity of shoreline and surrounding land use. Because of differences in the environmental conditions, mostly light availability, usage of buffer zone, among the three macrophyte groups, changes in biomass were analyzed in this work suggests that complementarity not competition drive the community. This phenomenon seems to occur only in macrophyte lakes where all three groups are present and the surrounding buffer zones remain natural. In lakes where one of the three groups of macrophytes were missing, it is likely that the ecological roles are fulfilled by other plant groups, such as phytoplankton. The studied lakes represent both phytoplanton and macrophyte type of lakes.
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Abstrakt

Changes in the land use structure, which are observed in recent years, generally indicate their negative impact on ecological quality considered in the landscape scale. Therefore, the aim of this study was to determine whether such a trend also applies to protected areas, such as land-scape parks (LP). As research areas four parks located within the Roztocze and Solska Forest (Poland) were selected. Three factors were analyzed as an surrogate indicators of the ecological quality: the degree of anthropogenic transformation of land cover forms, landscape diversity and the degree of landscape fragmentation. The study included data for the years 2004 and 2012 and was based on the GIS and orthophotomaps analysis. The results showed a lack of general trends for the whole analyzed region. The impact of changes in the land use structure on the ecological values can be defined as positive for Krasnobród LP and South Roztocze LP. In the case of Szczebrzeszyn LP and Solska Forest LP the impact is difficult to determine due to the different results obtained on the basis of selected indicators. Therefore, in order to totally illustrate the analyzed dependence the landscape structure in other periods of time should be analyzed, as well as the correlations between the defined changes and a variety of natural and cultural considerations.
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Abstrakt

Land cover change (LCC) is important to assess the land use/land cover changes with respect to the development activities like irrigation. The region selected for the study is Vaal Harts Irrigation Scheme (VHS) occupying an area of approximately 36, 325 hectares of irrigated land. The study was carried out using Land sat data of 1991, 2001, 2005 covering the area to assess the changes in land use/land cover for which supervised classification technique has been applied. The Normalized Difference Vegetation Index (NDVI) index was also done to assess vegetative change conditions during the period of investigation. By using the remote sensing images and with the support of GIS the spatial pattern of land use change of Vaal Harts Irrigation Scheme for 15 years was extracted and interpreted for the changes of scheme. Results showed that the spatial difference of land use change was obvious. The analysis reveals that 37.86% of additional land area has been brought under fallow land and thus less irrigation area (18.21%). There is an urgent need for management program to control the loss of irrigation land and therefore reclaim the damaged land in order to make the scheme more viable.
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Abstrakt

To investigate and assess the effects of land use and its changes on concentrations of heavy metals (Pb, Zn, Cd, Cu, Mn, Ni, Fe) in the tributary of drinking water reservoir catchment, soils of different land use types (forest, arable land, meadows and pastures, residential areas), suspended sediment and bottom sediment were collected. Heavy metals were analyzed using atomic absorption spectrophotometry (AAS). The metal distribution pattern was observed, where Zn and Cd could be considered as main metal contaminants. The variation in the concentration level of Zn and Cd in studied soils showed the impact of pollution from anthropogenic activities. Also some seasonal variations were visible among the suspended sediment and bottom sediment samples which could be associated with land agricultural practices or meteorological conditions. The sediment fingerprints approach used for determining sources of the suspension in the catchment showed (Kruskal-Wallis H test, p<0.05), that only Mn and Ni were not able to be distinguished among the potential sediment sources. A multiple linear regression model described the relationship between suspended sediment and 4 types of soil samples. The results related suspended composition mostly to the samples from the residential land use. Considering the contemporary trend of observed changes in land use resulting in conversion of agricultural areas into residential and service structures these changes can be essential for the contamination of aquatic environment. This situation is a warning sign due to the rapid industrialization, urbanization and intensive agriculture in this region what can significantly affect the drinking water quality.
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